This invention is related to the field of fumigation processes that use sulfuryl fluoride as a fumigant.
It is well known that insects and other pests are very destructive to property and that they can endanger human life. It has been estimated that termites alone cause more than 750 million dollars in damage every year, much of this damage is done to homes where families live.
Fumigation is the use of certain gases to control insects and other pests that are present in enclosed, or enclosable, areas where they are not desired, such as, family homes. Currently, the fumigant of choice is sulfuryl fluoride. The preferred source for sulfuryl fluoride is Dow AgroSciences LLC., which sells a specialty sulfuryl fluoride product under the trademark Vikane® gas fumigant.
During fumigation it is important to know the amount of sulfuryl fluoride in the air of the enclosed area. This is because a certain level of sulfuryl fluoride is needed in the air of the enclosed area in order to rid such area of the insects and other pests that are present therein. Consequently, a Fumiscope is used to determine this amount.
A Fumiscope is a portable instrument that will quantitatively measure the gas concentration in air by sampling the atmosphere of the enclosed area. However: there are certain problems with using a Fumiscope. In particular, most, if not all, Fumiscopes that measure sulfuryl fluoride are sensitive to the amount of water vapor in the air. That is, the amount of water vapor adversely affects the detection capabilities of the Fumiscope. One preferred method to overcome this problem is to use a drying material such as, anhydrous calcium sulfate to absorb the water vapor. However, this solution is not optimal. First, these types of dryers can remove other gases, such as sulfuryl fluoride, from the sample thereby making the Fumiscope give an inaccurate reading. Second, these types of dryers are used up during the monitoring, and consequently, the effectiveness of these dryers decreases over time and the baseline of the Fumiscope drifts. This means that the dryers must be replaced often during monitoring and the Fumiscope must be re-zeroed during monitoring in order to get accurate readings. These procedures are time consuming and labor-intensive and prevent the unattended operation of the Fumiscope.
Consequently, in light of the above the inventors provide the following solution to this problem.